Liam walker



(No Model.)

l J. GOCHRANE & W. WALKER.

PUMPING ENGINE- Patented Nov. 20, 1894.

UNI ED ST TEs PATENT "Or fice.

JOHN COCHRANE, OF BARRHEAD, NEAR GLASGOW, SCOTLAND, AND WIL- LIAM WALKER, OF SALFORD, MANCHESTER, ENGLAND; SAID WALKE AssIcNon TO SAID COCHRANE.

PUMPING-ENGINE.

SPECIFICATION forming part of Letters Patent No. 529,678, dated November 20, 1894. Application filed October 13, 1893. Serial No. 488,022- (No model.) Patented in England October 17, 189 1, Nil-" 71 To all whom it may concern.-

Be it known that we, JOHN COOHRANE,6[1- gineer, residing at Barrhead,'near Glasgow, Scotland, and WILLIAM WALKER, mechanical engineer, residing at 12 Holly Street, Eccles New Road, Salford, Manchester, England, have invented certain new and useful Improvements in Reciprocating Engines, (for which we have obtained Letters Patent in Great Britain, No. 17,805, dated October 17, 1891,) of which the following is a specification.

Our invention relates to direct acting reciprocating engines and to means for operating the valves of the cylinder, for the purpose of reversing the motion of the main piston of the said cylinder, at or near the end of each stroke and producing a reciprocating action without the aid of a fly-wheel. We use by preference an ordinary three ported'cylinder, and above it is formed an auxiliary steam cylinder which is bored out to receive a cylindrical and an auxiliary distributing valve for the purpose of distributing steam or fluid to the said main piston. The said cylindrical valve is made in this instance to reciprocate in the same longitudinal plane 'as the said mainpiston and the outer endsof the said cylindrical valve are closed, so asto fulfill the functions of pistons, as each end of the same is operated upon alternately by steam or fluid pressure, for the aforesaid purpose of distributing such steam or fluid pressure to one side.

or the other of the main piston as the case may be. The manner in which this is eflected is as follows:To the piston rod of the engine, between the pump and the cylinder glands, we attach a light connecting rod, and the said connecting rod is made to give a vibrating or plug and casing.

in the said auxiliary val've'plug, and they are so arranged as to give steam to one end or the other of the cylindrical valve, and simultaneously place the oppositeend thereof in direct communication with the main exhaust passage of the engine. The said rock-shaft is made to fulfill another duty, besides simply acting asa means for rocking the auxiliary distributing valve. The manner and purpose for which it is used is as follows:-A tongue or projection is formed'on the said rock-shaft, and the said tongue or projection is of sufficient length to reach suitable projections formed on the inside of the said cylindrical valve in one direction or the other at each end of the stroke of the main piston, whereby the saidcylindrical valve would be forced or pushed over in either direction, thereby insuring a positive reversal of the main piston, in

showing the exhaust portsleading from either end of the cylindrical valve. Fig. 4 is a detail sectional view of the auxiliary valve-plug and casing and the adjacent} parts,and showing the steam admission portsto either end Y of the cylindrical valve for flashing it over. Fig. 5 is an end View of the auxiliary valveplug and casing, and showing the inner end of the rock-shaft for oscillating'the said valve- Figs. 6, 7 and 8 are respectively detail views of the rock-shaft. Figs. 9 and 10 are respectively detail views of the auxiliary valve casing and plug.

Referring to the said drawing: A represents the main piston cylinder, provided with the steam inlet passages Q, Q, and the exhaust passage F, and M the piston head working therein and provided with the piston rod A.

A represents the auxiliary steam cylinder, which contains the cylindrical valve N, and the auxiliary distributing valve plug and easing E, P. The ends of the cylindrical valve are closed as will be seen in Fig. 1, to permit of the steam as it is admitted to either end flashing itover.

.Iournaled with the auxiliary steam cylinder is the rock-shaft D formed with the projections Y and W. The projection W engages the cylindrical valve N at K, and K, the object of whichis to insure the flashing of the said valve when the engine is running at high speed, while the projection Y engages in an enlarged slot R in the valve plug E to change the position of the steam entrance ports during the operation of the engine. The slot R (see Fig. 5) is enlarged in order to. pemnitof a lost motion or period of rest for the valve-plug before the main piston reaches the end of its stroke and it is neces: sary tochange the position of the valve-plug, within the casing P. This said casing is provided with a number of ports for the admission and exhaust of steam as will be seen in Fig. 9. This rocking motion of theshaft D is obtained through the medium of the swinging lever O which is keyed to the shaft 1) and which is connected to the piston rod A by means of the connecting link B.

The operation of our engine is as follows: As the engine is started steam is admitted through the supply port S to the opening S in the valve-plug casing P, and to the valveplu g E, through the passage X to one end of the valve N, (see Fig. 4,) which flashes the said valve over and allows steam to enter the main cylinder through one of the passages Q, Q. At the same time steam is being exhausted from the other end of the valve N,

through the passage X and the passage in the valve-plug E, through the main exhaust F. (See Fig. 3.) As the piston M is nearing the end of its stroke, the valve-plug E is turned by the projection Y on the rock-shaft D, which is rocked by the swinging lever connected with the piston rod so as to change the ports. In this position steam is admitted to the other end of the valve N through the passages in the Valve-plug E and the passage X while at the same time the steam is exhausting from the other end of the valve N through the passage X to the main exhaust F. As the piston M is again nearing the end of its stroke the projection Y again changes the position of the passages and the valve-plug E.

Having thus described our invention, the following is what we claim as new therein and desire to secure by Letters Patent:

In a reciprocating engine, the combination of the main cylinder and piston,an auxiliary steam cylinder located above the main cylinder, a reciprccating cylindrical valve and an auxiliary distributing valve, located at right angles to the reciprocating valve working in said auxiliary cylinder, a rock-shaft journaled in said auxiliary cylinder in line with the distributing valve and having a projection for engagement with the said valve, and a second projection for engagement with the reciprocating cylindrical valve,and a suitable connection between the rock-shaft and piston substantially asand for the purpose set forth.

In testimony whereof we have signed our names to this specification in the presence of four subscribing witnesses.

JOl-IN CO CI-IRANE. WILLIAM \VALKER. Witnesses to the signature of John Cochrane:

JOSEPH MCMILLAN, JOHN M ODONALD, Both of 123 St. Vincent St, GlasgomSoZicitors Clerks.

Vt itnesses to the signature of Villiam Walker:

J OHN I-IUroHEsoN, Timber Merchit, Ba'rrhead.

GEORGE HAnRIsoN, J oiner, Bm'rheacl. 

